This invention relates to a transportable data input/output unit capable of being detached from the body of a numerical control device.
In numerical control, there are cases where a host computer is used to perform a variety of data processing operations to create command data for the machining of a workpiece. The data created by the host computer is recorded on a paper tape by a tape puncher and, with the paper tape serving as the recording medium, is used as input information for another system. In creating the paper tape, the contents of the tape are printed out by a printer in order to provide a record thereof beforehand. Where an output from the host computer is recorded on the paper tape or printed on recording paper, the paper tape puncher and printer ordinarily are provided separately from the host computer body. These pieces of equipment are connected to the host computer and operate solely in response to commands therefrom. Unlike a system in which such peripheral equipment is of a disjointed nature, a system is conceivable in which the equipment operates on the basis of commands from a host computer when connected to the computer, but in which the contents of a paper tape may be read independently and printed for copying purposes when the equipment is disconnected from the host computer. However, a system of such type can be applied to only very limited systems and is inapplicable to others in certain aspects. Moreover, even where applicable, a disadvantage is that results cannot be obtained unless the host computer software is modified. Furthermore, when printing is performed by a printer, it is customary to print out the first character starting from the left margin of the printing paper. In cases where the printing paper is bound on the left side after printing, some inconvenience is experienced as there is not enough room left on the left side of the paper.